The “real” medium of commonsense

Suppose your friend told you - I gave a book to John. You will make commonsense implications from the above sentence, like for example - which book did he give to John? Whose (author) book was it? etc. But what made you believe or assume in the first place that the book was a standard book (one with a title, author, price, publisher etc.)? It is the whole medium that you are in, experiencing that reality (the data) which puts you in a certain frame of mind of making fundamental assumptions about everything that you see in that medium. It can be very indirect. Because you know a real, typical human being (your friend) gave a book to another real, typical human being that you subconsciously believed that the item given was also a real, typical, commonsense-satisfying, standard entity i.e. the book. You were convinced of the standardness of the experience (friend telling you about his friend) and that effect spilled over onto the whole data (including the book), i.e. you assumed the book to be a standard one from the surrounding standard scenario of two real, typical human beings transferring something between them. Per se there is no need of believing that the book was a standard one (it could have been one without a publisher or without any cost or whatever - say a memoir of Marvin Minsky prepard by his students and distributed in the department). But because you are “in that medium of ‘reality’ which you are convinced of being so in by the mental registry of the fact that you are actually listening to some real person narrating something to you in person, and where you know that thus commonsense applies, that you apply that state of mind to the book also. Using commonsense is something like “being immersed in the medium, at various root-levels”.